Generation and characterization of KiPS cells from a single plucked hair.
(a) The internal part of a single scalp hair was placed in ES cell medium.
(b) Outgrowth of keratinocytes from the outer root sheet after 5d

The utility of induced pluripotent stem (iPS) cells for investigating the molecular logic of pluripotency and for eventual clinical application is limited by the low efficiency of current methods for reprogramming. Our methods can yield at least 100-fold more efficient and twofold faster production of iPS cells compared with reprogramming of human fibroblasts. Keratinocyte-derived iPS (KiPS) cells appear indistinguishable from human embryonic stem cells in colony morphology, growth properties, expression of pluripotency-associated transcription factors and surface markers, global gene expression profiles and differentiation potential in vitro and in vivo.

To underscore the efficiency and practicability of this technology, we can also generate KiPS cells from single adult human hairs. Our findings provide an experimental model for investigating the bases of cellular reprogramming and highlight potential advantages of using keratinocytes to generate patient-specific iPS cells.